From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1835C46470 for ; Tue, 7 Aug 2018 08:54:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 74D13208CB for ; Tue, 7 Aug 2018 08:54:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 74D13208CB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387958AbeHGLHj (ORCPT ); Tue, 7 Aug 2018 07:07:39 -0400 Received: from foss.arm.com ([217.140.101.70]:51192 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387702AbeHGLHj (ORCPT ); Tue, 7 Aug 2018 07:07:39 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 22A5815AB; Tue, 7 Aug 2018 01:54:21 -0700 (PDT) Received: from approximate.Emea.Arm.com (approximate.Emea.Arm.com [10.4.13.119]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C286B3F5D4; Tue, 7 Aug 2018 01:54:19 -0700 (PDT) From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Cc: Joerg Roedel , Heiko Stuebner , Jeffy Chen Subject: [PATCH 2/2] iommu/rockchip: Move irq request past pm_runtime_enable Date: Tue, 7 Aug 2018 09:54:06 +0100 Message-Id: <20180807085406.3863-3-marc.zyngier@arm.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180807085406.3863-1-marc.zyngier@arm.com> References: <20180807085406.3863-1-marc.zyngier@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Enabling the interrupt early, before power has been applied to the device, can result in an interrupt being delivered too early if: - the IOMMU shares an interrupt with a VOP - the VOP has a pending interrupt (after a kexec, for example) In these conditions, we end-up taking the interrupt without the IOMMU being ready to handle the interrupt (not powered on). Moving the interrupt request past the pm_runtime_enable() call makes sure we can at least access the IOMMU registers. Note that this is only a partial fix, and that the VOP interrupt will still be screaming until the VOP driver kicks in, which advocates for a more synchronized interrupt enabling/disabling approach. Fixes: 0f181d3cf7d98 ("iommu/rockchip: Add runtime PM support") Signed-off-by: Marc Zyngier --- drivers/iommu/rockchip-iommu.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c index 4e0f9b61cd7f..2b1724e8d307 100644 --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -1161,17 +1161,6 @@ static int rk_iommu_probe(struct platform_device *pdev) if (iommu->num_mmu == 0) return PTR_ERR(iommu->bases[0]); - i = 0; - while ((irq = platform_get_irq(pdev, i++)) != -ENXIO) { - if (irq < 0) - return irq; - - err = devm_request_irq(iommu->dev, irq, rk_iommu_irq, - IRQF_SHARED, dev_name(dev), iommu); - if (err) - return err; - } - iommu->reset_disabled = device_property_read_bool(dev, "rockchip,disable-mmu-reset"); @@ -1228,6 +1217,19 @@ static int rk_iommu_probe(struct platform_device *pdev) pm_runtime_enable(dev); + i = 0; + while ((irq = platform_get_irq(pdev, i++)) != -ENXIO) { + if (irq < 0) + return irq; + + err = devm_request_irq(iommu->dev, irq, rk_iommu_irq, + IRQF_SHARED, dev_name(dev), iommu); + if (err) { + pm_runtime_disable(dev); + goto err_remove_sysfs; + } + } + return 0; err_remove_sysfs: iommu_device_sysfs_remove(&iommu->iommu); -- 2.18.0